JPH0755901A - Discharge capacity testing method for series connection set battery - Google Patents

Abstract

PURPOSE:To test without trouble in a backup function by connecting redundantly one or more secondary cell rows to constitute a set battery, and providing bypass routes in the respective rows. CONSTITUTION:A set battery B1 having one redundant secondary cell row (hereinafter referred to as 'a row') is fully charged. When a switch SW S1 is switched from a terminal X to a terminal Y from this state, a charge current of the row A1 flows to a discharge capacity measuring circuit J, and a retained electric energy of the row A1 is measured. After a discharge test is finished, the SW S1 is switched to the terminal X, and the row A1 is again charged from a charging circuit C. Then, when SWs S2a and S2b are switched to the terminal Y, a current of a row A2 flows to the circuit J, and a retained electric energy of the row A2 is measured. The SWs S2a and S2b are switched to the terminal X, and the row A2 is again charged. Similarly, rows A3-An are sequentially conducted in series of operations, and a discharge capacity test of the entire battery B1 is conducted. When a sum total of the power capacity of the rows A1-An is obtained, the power capacity of the entire battery B1 can be measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a battery pack for a power failure backup power supply, and more particularly to a method for testing the discharge capacity of a series-connected battery pack that automatically measures the amount of power stored in the battery while continuing the backup function. It is a thing.

[0002]

2. Description of the Related Art FIG. 5 is a circuit diagram showing an example of a conventional power failure backup power supply.

In this conventional example, secondary battery cells are connected in series to form a secondary battery cell array A1, A2, A3,
Secondary battery cell rows A1, A2, A3 are connected in series to form an assembled battery B. The charging circuit C matches the voltage of the input power source E with the voltage for charging the secondary battery cell arrays A1, A2, A3, and the output voltage stabilizing circuit S stabilizes the voltage supplied to the load L. There is.

In this conventional example, in a normal state (a state in which the voltage of the input power source E is normal), the charging circuit C inputs a voltage suitable for charging the secondary battery cell rows A1 to A3 in the assembled battery B. The output voltage of the power source E is matched, the assembled battery B is charged, and in the power failure state (the state where the input power source E is stopped), the assembled battery B supplies power to the load L, and
The output voltage stabilizing circuit S matches the terminal voltage of the assembled battery B with the voltage required by the load L and outputs the voltage.

The battery pack B is obtained by multiplying the sum of the power required by the load L and the power loss consumed by the output voltage stabilizing circuit S by the allowable blackout duration to be guaranteed. Must have the required power capacity. further,
Since the maximum power capacity of the secondary battery cells that form the battery pack B decreases over time due to deterioration over time, the initial power capacity that includes an extra amount of power capacity that deteriorates and decreases during the required period from the beginning. Must be prepared in the assembled battery B. By configuring the assembled battery in this way, the backup power supply can continue the allowable power outage duration and the power outage backup in the required period.

[0006]

By the way, since the characteristics of the deterioration of the secondary battery cell are affected by the temperature and humidity environmental conditions in which the secondary battery cell is placed, the number of times of charging and discharging, etc. Whether or not the power held by the battery B actually holds the required power capacity cannot be determined unless the discharge capacity test (measurement of the amount of power held) is performed by actually discharging the battery pack B. . In this case, when the assembled battery B is discharged for the discharge capacity test, the backup function is lowered or stopped until the recharge of the assembled battery B is completed.

In the above conventional example, in order to prevent the backup function from being deteriorated or stopped during the discharge capacity test,
Battery B during the discharge capacity test or immediately after that test
In order not to cause trouble even if a power failure occurs while the battery pack is not recharged, a charged battery pack having a power capacity equal to or higher than that of the battery pack B is prepared in advance as a spare, and this spare battery pack is used. The discharge capacity test is performed after the battery and the actual assembled battery B are exchanged or connected in parallel. However, when the spare battery pack and the actual battery pack B are exchanged or connected in parallel as described above and then the discharge capacity test is carried out,
There is a problem that the cost of the spare assembled battery increases and the installation space increases.

According to the present invention, even if a spare assembled battery is not provided,
An object of the present invention is to provide a discharge capacity test method for series-connected assembled batteries that can ensure a backup function.

[0009]

According to a first aspect of the present invention, an assembled battery is constructed so that at least one secondary battery cell column is redundantly connected in series, and the assembled battery is charged and then the assembled battery is charged. A secondary battery cell array of a number equal to or less than the redundant number is selected, and a path that bypasses the selected secondary battery cell array is provided so as to form a path for the current output from the assembled battery. The next battery cell row is disconnected from the assembled battery and selected
This is a method of obtaining the amount of electric power held by the selected secondary battery cell row by measuring the amount of electric power discharged when the secondary battery cell row is discharged.

According to a second aspect of the present invention, in addition to the first aspect of the invention, after the discharged secondary battery cell array is connected to the assembled battery, the bypass route is released, and recharged, 2 other than the rechargeable battery cell row for which the above-mentioned stored power amount was obtained
For each secondary battery cell row, installation of a bypass path, disconnection from the assembled battery, discharge, measurement of discharge electric energy,
This is a method of performing a discharge capacity test of the entire assembled battery by sequentially performing a series of operations of connecting into the assembled battery, releasing the bypass path, and recharging.

[0011]

According to the first aspect of the present invention, the assembled battery is configured so that at least one secondary battery cell row is redundantly connected in series, and after the assembled battery is charged, the number of redundant batteries in the assembled battery is equal to or less than the redundant number. Of 2
When a secondary battery cell row is selected, a path that bypasses the selected secondary battery cell row is provided, the selected secondary battery cell row is disconnected from the assembled battery, and the selected secondary battery cell row is discharged Since the amount of electric power possessed by the selected secondary battery cell row is obtained by measuring the amount of electric power discharged, the backup function of the assembled battery can be ensured without providing a spare assembled battery. If a plurality of rechargeable battery cell arrays that form an assembled battery are installed at the same time, the discharge capacities of the rechargeable battery cell arrays are often almost the same, so that only one rechargeable battery cell array is installed. If the discharge amount is measured, the discharge amount is measured, and the discharge amounts of the other secondary battery cell rows are also the same, it is easy to measure the discharge capacity of the entire assembled battery.

According to a second aspect of the present invention, for all the secondary battery cell rows, installation of bypass paths, disconnection from the assembled battery, discharge, measurement of discharged power amount, connection to the assembled battery,
Since the discharge capacity test of the entire assembled battery is performed by sequentially performing a series of operations of releasing the bypass path and recharging, it is possible to secure the backup function of the assembled battery without providing a spare assembled battery. In addition, more reliable discharge capacity measurement data can be obtained.

[0013]

1 is a circuit diagram showing a first embodiment of the present invention.

In the first embodiment, a secondary battery cell array A1 composed of a plurality of secondary battery cells connected in series with each other,
The assembled battery B1 is configured by connecting A2 and A3 to An in series, and the power accumulated in the assembled battery B1 is a power failure backup power source that guarantees the continuity of the power source. One secondary battery cell column is redundant so that a backup operation for a predetermined time can be performed even if one of An is excluded.

The charging circuit C is a circuit for matching the output voltage of the input power source E with the voltage for charging the secondary battery cell arrays A1 to An by raising or lowering the output voltage of the input power source E. The output voltage stabilizing circuit S is a circuit that stabilizes the voltage supplied to the load L. Discharge capacity measuring circuit J
Is a circuit for measuring the discharge capacity of the secondary battery cell row being discharged. For example, the current value when a discharge current is applied to a predetermined load (not shown), the voltage across the load, and the discharge time. The power capacity is measured based on the above, and this measurement data is output.

Bypass diodes D1, D2, D3 to D
n is the secondary battery cell row A1, A2, A3 to A, respectively.
n is a diode to be connected in parallel, and when one of the secondary battery cell arrays A1 to An is separated from the assembled battery B1, the separated secondary battery cell array The secondary battery cell rows except for form a passage for the current output from the assembled battery B1 so that the secondary battery cell row can supply the current to the load L.

The switch S1 disconnects the secondary battery cell array A1 from the assembled battery B1 and separates the secondary battery cell array A.
1 is connected to the discharge capacity measuring circuit J, and the switches S2a and S2b connect the secondary battery cell row A2 to the assembled battery B.
1 and the secondary battery cell array A2 that has been separated is connected to the discharge capacity measuring circuit J.
3a and S3b disconnect the secondary battery cell array A3 from the assembled battery B1 and connect the separated secondary battery cell array A3 to the discharge capacity measuring circuit J.
Snb disconnects the secondary battery cell array An from the assembled battery B1 and connects the separated secondary battery cell array An to the discharge capacity measuring circuit J.

That is, the switching contact of the switch S1 is connected to the + terminal of the secondary battery cell array A1, the contact X of the switch S1 is connected to the cathode terminal of the diode D1, and the contact Y of the switch S1 is the discharge capacity measuring circuit. It is connected to J. Further, the switching contact of the switch S2a is connected to the positive terminal of the secondary battery cell array A2, and the contact X of the switch S2a is connected.
Is connected to the cathode terminal of the diode D2 and the anode terminal of the diode D3, the contact Y of the switch S2a is connected to the discharge capacity measuring circuit J, and the switching contact of the switch S2b is connected to the negative terminal of the secondary battery cell row A2. The contact X of the switch S2b is connected to the anode terminal of the diode D2 and the anode terminal of the diode D4, and the contact Y of the switch S2b is connected to the negative side terminal of the input power source E.

The switches S3a to S3n are the switches S2.
The switches S3b to Snb are connected in the same manner as a, and the switches S3b to Snb are connected in the same manner as the switch S2b. The switch S
Switches such as 3a and S3b that have the same number following "S" are switched at the same time, and if one switch is connected to the X contact, the other switch is also connected to the X contact. There is.

The switch for switching the secondary battery cell array A1 is only the switch S1. This is because the switch on the minus side is omitted due to the potential relationship in the above circuit configuration.

Next, the operation of the above embodiment will be described.

First, the switches S1, S2a to Sna, S.
All of 2b to Sn are switched to the terminal X, and if the output voltage of the input power source E is normal, the charging circuit C charges this output voltage to the secondary battery cell rows A1 to An in the assembled battery B1. Charge to match the appropriate voltage. As a result, the assembled battery B1 is finally fully charged (the assembled battery B1 is in a fully charged state).

In this fully charged state, a discharge capacity test is performed on any one secondary battery cell array in the assembled battery B1, for example, the secondary battery cell array A1. That is, the switch S
Only 1 is switched from terminal X to terminal Y. As a result, the charging current of the secondary battery cell array A1 flows into the discharge capacity measuring circuit J, and the discharge capacity measuring circuit J measures the amount of power held in the secondary battery cell array A1.

During this discharge capacity test, the secondary battery cell array A1 is separated from the assembled battery B1, but the diode D1 forms a discharge current path to the load L of the assembled battery B1, and one Since the next battery cell row is set to be redundant, there is no problem in backup of power failure.

After the discharging test of the secondary battery cell array A1 is completed, the switch S1 is switched to the X terminal, and the charging circuit C charges the secondary battery cell array A1 again. If the assembled battery B1 is charged by, for example, trickle charging, it is not necessary to charge the connection of the secondary battery cell array A1 before returning to the assembled battery B1. Is formed, the diode D
1 is reverse biased and the discharge bypass current path is cut off,
The supply of the charging current from the charging circuit C is restarted, and the charging of the secondary battery cell array A1 is started.

Immediately after the secondary battery cell array A1 used in the discharge capacity test is returned to the assembled battery B1, and when the secondary battery cell array A1 is not completely charged, a power failure occurs, The secondary battery cell array A1 is completely discharged, and a current is passed until the voltage across the secondary battery cell becomes zero. After that, the diode D1 conducts and the discharge current is bypassed from the secondary battery cell array A1. There is no danger that the secondary battery cell array A1 is reversely charged by discharging the other secondary battery cell arrays A2 to An.

After the charging of the secondary battery cell array A1 is completed, another secondary battery cell array, for example, the secondary battery cell array A2, is subjected to a discharge capacity test. In this case, both the switches S2a and S2b are switched from the terminal X to the terminal Y. As a result, the charging current of the secondary battery cell array A2 flows into the discharge capacity measuring circuit J, and the discharge capacity measuring circuit J measures the amount of power held in the secondary battery cell array A2.

Next, for the secondary battery cell array A3, the corresponding two switches S3a and S3b are switched to disconnect the secondary battery cell array A3 from the assembled battery B1, discharge the battery, measure the discharged power amount, and A series of operations of connecting to the battery B1 and recharging is executed, and the secondary battery cell rows A4 to An are executed.
Similarly to each of the secondary battery cell arrays A2 and A3, the corresponding two switches are switched to disconnect the secondary battery cell array from the assembled battery B1, discharge the battery, measure the discharged power amount, and The entire discharge capacity test of the assembled battery B1 is performed by executing a series of operations of connecting to the inside of B1 and recharging.

In this way, finally, the power capacities of all the secondary battery cell arrays A1 to An in the assembled battery B1 are measured and the total power capacities of the secondary battery cell arrays A1 to An are obtained. Thus, the power capacity of the entire assembled battery B1 can be measured.

Therefore, in the first embodiment described above,
The discharge capacity can be reliably measured for all the secondary battery cell rows in the assembled battery B1, and the secondary battery cell row for which the discharge capacity measurement is performed has a redundant configuration. Therefore, during or immediately after the discharge capacity test. Therefore, even if the input power supply E is stopped when recharging is not completed, the backup function can be guaranteed for the required period, and the cost does not increase as much as the spare battery pack, and the installation space does not increase. Few.

In the above embodiment, when the assembled battery B1 is fully charged, the discharge capacity test is conducted only for one secondary battery cell row in the assembled battery B1.
When 1 is fully charged, the discharge capacity test may be simultaneously performed on two or more secondary battery cell rows.
However, the number of secondary battery cell rows that are simultaneously subjected to the discharge capacity test needs to be equal to or less than the redundant number of secondary battery cell rows.

In the above embodiment, a plurality of secondary battery cells are connected in series to form a secondary battery cell array, but a plurality of secondary battery cells are connected in series and parallel to each other. You may make it comprise a row. In the above-described embodiment, the secondary battery cell array is composed of a plurality of secondary battery cells, but one secondary battery cell may be composed of the secondary battery cell array.
Further, in the above embodiment, n secondary battery cell rows A1 to An are provided, but this n is an arbitrary number, and two secondary battery cell rows may be provided, or three secondary battery cell rows may be provided. Alternatively, the redundant number of secondary battery cell rows may be two or more.

That is, in the first embodiment, the assembled battery is constructed so that one or more secondary battery cell rows are redundantly connected in series, and after the assembled battery is charged, the redundant number in the assembled battery is increased. The following secondary battery cell array is selected, and a path that bypasses the selected secondary battery cell array is provided so as to form a passage for the current output from the assembled battery, and the selected secondary battery cell array is connected. By measuring the discharge power amount when the selected secondary battery cell column is discharged after being separated from the assembled battery, the stored power amount of the selected secondary battery cell column is obtained, and the stored secondary battery cell column is discharged.
Regarding the next battery cell row, after the connection to the assembled battery, the release of the bypass route, and the recharging, the stored electric energy was calculated 2
For each of the secondary battery cell rows other than the secondary battery cell row, installation of the bypass path, disconnection from the assembled battery, discharge, measurement of the discharged power amount, connection into the assembled battery, connection of the bypass path The discharge capacity test of the entire assembled battery is performed by sequentially executing a series of operations of releasing and recharging.

Further, in the above embodiment, the switches S1, S2a to Sna, S2b to Snb are shown as mechanical switches, but these switches S
1, S2a to Sna, S2b to Snb may be electronic switches configured by transistors or the like, and may be switched and controlled by a command from a microcomputer or the like.

FIG. 2 is a circuit diagram showing a second embodiment of the present invention.

This second embodiment is basically the same as the first embodiment shown in FIG. 1, but switches S1, S3a to Sna, S3b to Snb and diodes D1, D3 to Dn in the first embodiment. Are deleted, and the secondary battery cell rows A3 to A
n are connected in series, and are connected via switches S2a and S2b.
The difference is that the secondary battery cell arrays A1, A2, and A3 are connected in series, and the discharge capacity measuring circuit J is connected only to the secondary battery cell array A2 via the switches S2a and S2b.

In the second embodiment shown in FIG. 2, first,
Switch S2a and S2b to the X terminal,
If the output voltage of the input power source E is normal, this output voltage is transformed into an appropriate voltage by the charging circuit C, the secondary battery cell arrays A1 to An are charged, and the assembled battery B1 is fully charged.
In this fully charged state, the switches S2a and S2b are switched to the Y terminal in order to perform the discharge capacity test on the secondary battery cell array A2. As a result, the charging current of the secondary battery cell array A2 flows into the discharge capacity measuring circuit J, and the discharge capacity measuring circuit J measures the amount of power held in the secondary battery cell array A2.

In this case, if the secondary battery cell arrays A1 to An forming the assembled battery B1 are installed at the same time, the discharge capacities of the secondary battery cell arrays A1 to An are often substantially the same. Therefore, if only one secondary battery cell array A2 is discharged, the discharge amount is measured, and the discharge amounts of the other secondary battery cell arrays are also the same, it is easy to measure the discharge capacity. is there. Moreover, since the secondary battery cell array A2 in the assembled battery B1 has a redundant configuration, even if the input power supply E is stopped during the discharge capacity test or immediately after that, and when recharging is not completed, The backup function can be guaranteed.

That is, in the second embodiment, the assembled battery is constructed so that one or more secondary battery cell rows are redundantly connected in series, and after the assembled battery is charged, the redundant number in the assembled battery is increased. The following secondary battery cell array is selected, and a path that bypasses the selected secondary battery cell array is provided so as to form a passage for the current output from the assembled battery, and the selected secondary battery cell array is connected. By measuring the discharge power amount when the selected secondary battery cell column is discharged after being separated from the assembled battery, the retained power amount of the selected secondary battery cell column is obtained.

FIG. 3 is a circuit diagram showing a modification of the first embodiment shown in FIG.

In this modification, the secondary battery cell rows A1 to An are used.
This is an example improved so that charging of secondary battery cell rows other than the secondary battery cell row subjected to the discharge capacity test can be continued even during the discharge capacity test. That is, instead of the diodes D1 to Dn in FIG. 1, the secondary battery cell rows A1 to
The constant voltage diodes D1z to Dnz having a breakdown voltage higher than the maximum terminal voltage of An are provided.

Thereby, for example, the secondary battery cell array A
2 is connected in series to the breakdown voltage of the constant voltage diode D2z and the constant voltage diode D2z even if 2 is separated by the switches S2a and S2b for the discharge capacity test.
If the charging circuit C supplies a voltage exceeding the sum of the terminal voltages of the secondary battery cell arrays A1, A3 to An, the charging current path is secured via the constant voltage diode D2z. Therefore, even when the secondary battery cell array A2 is being tested for discharge capacity, the battery packs other than the secondary battery cell array A2 that are to be subjected to the discharge capacity test cannot
The charging of the next battery cell row A1, A3 to An can be continued.
In addition, when a secondary battery cell array other than the secondary battery cell array A2 is disconnected from the assembled battery B1 for the discharge capacity test,
The same as above. In addition, the operation other than the above-mentioned operation is shown in FIG.
The operation is the same as that of the first embodiment shown in FIG.

FIG. 4 is a circuit diagram showing a modification of the second embodiment shown in FIG.

This modification is improved so that the secondary battery cell rows other than the secondary battery cell row subjected to the discharge capacity test can be continuously charged even during the discharge capacity test of the secondary battery cell row A2. Here is an example. That is, instead of the diode D2 in FIG. 2, a constant voltage diode D having a breakdown voltage higher than the maximum terminal voltage of the secondary battery cell rows A1 to An.
2z is provided.

Also in this case, even if the secondary battery cell array A2 is disconnected by the switches S2a and S2b for the discharge capacity test, the breakdown voltage of the constant voltage diode D2z and the constant voltage diode D2z are connected in series. If the charging circuit C supplies a voltage exceeding the sum of the terminal voltages of the secondary battery cell rows A1, A3 to An, the constant voltage diode D2z.
A charging current path is secured through the secondary battery cell array A2
Even during the discharge capacity test, the secondary battery cell arrays A1 and A3 other than the secondary battery cell array A2 subjected to the discharge capacity test.
~ An can be continuously charged.

[0046]

According to the invention described in claim 1, the backup function of the assembled battery can be ensured without providing a spare assembled battery, and only one secondary battery cell row is discharged. If the amount of discharge at that time is measured and it is estimated that the amounts of discharge of the other secondary battery cell rows are also the same, it is possible to easily measure the discharge capacity.

According to the second aspect of the invention, the backup function of the assembled battery can be ensured without providing a spare assembled battery, and more reliable discharge capacity measurement data can be obtained. Has the effect.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a second embodiment of the present invention.

FIG. 3 is a circuit diagram showing a modification of the first embodiment.

FIG. 4 is a circuit diagram showing a modification of the second embodiment.

FIG. 5 is a circuit diagram showing an example of a conventional power failure backup power supply.

[Explanation of symbols]

E ... Input power supply, C ... Charging circuit, S ... Output voltage stabilizing circuit, L ... Load, B1 ... Battery pack, J ... Discharge capacity measuring circuit, S1, S1a to Sna, S1b to Snb ... Changeover switch, X, Y ... contacts of the changeover switch, A1 to An ... secondary battery cell arrays that form the assembled battery B1, D1 to Dn ... current bypass diodes, D1z to Dnz ... constant voltage diodes as current bypass diodes.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Yamashita 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (2)

[Claims] 1. An assembled battery is formed by connecting a plurality of secondary battery cell rows each including one or a plurality of secondary battery cells in series, and the power stored in the assembled battery is used as a power source. In a power failure backup power supply that guarantees sustainability, the assembled battery is configured so that one or more secondary battery cell rows are redundantly connected in series, and the redundant battery in the assembled battery is charged after charging the assembled battery. The number of the secondary battery cell rows is selected to be equal to or less than a certain number, and a path for bypassing the selected secondary battery cell rows is provided so as to form a passage of the current output from the assembled battery, and the selected secondary battery cell row is selected. Determining the amount of power held by the selected secondary battery cell array by disconnecting the secondary battery cell array from the assembled battery and measuring the amount of discharge power when the selected secondary battery cell array is discharged. Characterized by Discharge capacity test method of the connection assembled battery. 2. The stored electric energy of the selected secondary battery cell array is obtained by measuring the amount of electric power discharged when the selected secondary battery cell array is discharged, according to claim 1, Regarding the rechargeable battery cell array, after the connection into the assembled battery, the release of the bypass route, and the recharging, the above-mentioned stored power amount was calculated 2
For each of the secondary battery cell rows other than the secondary battery cell row, installation of the bypass path, disconnection from the assembled battery, discharge, measurement of the discharged power amount, connection into the assembled battery, connection of the bypass path A discharge capacity test method for a series-connected assembled battery, wherein a discharge capacity test of the entire assembled battery is performed by sequentially executing a series of operations of releasing and recharging.